Respirator



Sept. 12, 1961 J. N. MATHESON 2,999,498

RESPIRATOR Filed May 7, 1957 2 Sheets-Sheet 1 v INVENTOR.

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Sept. 12, 1961 J. N. MATHESON 2,999,498

RESPIRATOR Filed May 7, 1957 2 Sheets-Sheet 2 INVENTOR.Mesflfllllzesorz.

United States Patent 2,999,498 RESPIRATOR James N. Matheson, Reading,Pa, assignor, by mesne assignments, to The Electric Storage BatteryCompany, Philadelphia, Pa., a corporation of New Jersey Filed May 7,1957, Ser. No. 657,671

Claims. (Cl. 128--146) This invention relates to an industrialrespirator for filtering dust and obnoxious fumes and, moreparticularly,

to a respirator face piece having replaceable filters and which isadapted to surround the nose, cheeks and chin of the wearer. This is acontinuation-in-part of my copending application Serial No. 430,488filed May 18, 1954, .now Patent No. 2,858,828. 7

An outstanding disadvantage of common types of industrial respiratorface pieces is that they include inhalation valves which offerappreciable resistance to breathing, therefore tire the wearer.

Another disadvantage is that the exhalation valve sometimes becomesleaky because of the failure ofthe valve diaphragm to become securelyseated on the valve seat, particularly when there are imperfectionseither in the diaphragm or seat or when dust particles are introducedbetween the diaphragm and seat.

An object of my invention is to provide a novel res pirator face piecewhich is devoid of the above named disadvantages and which includesinhalation valves which provide minimum breathing resistance and willassure a positive seal of the valve even in the event there areimperfections in the valve diaphragm or seat or if dust particles areintroduced therebetween.

A more specific object of my invention is to provide anovel inhalationvalve mounting for the valve diaphragm for easy flexing to the openposition on inhalation, and which will assure an air-tight seal with the'valve se'at minimum resistance to exhalation as well as quick andpositive seating in an air-tight manner'upon inhalation of the wearereven in cases where there are imperfections in the seat or diaphragm, orif dust particles are introduced between the valve elements. a

Another object of my invention is to provide a unitary industrialrespirator face piece including a pleated nose piece constructed in amanner so as to provide a comfortable, cushioned fit, particularlyaround the nose of the wearer.

Other objects and advantages of my invention will become more apparentfrom a study of the following description taken with the accompanyingdrawings wherein:

FIG. 1 is a front elevational view. of an industrial respiratorembodying the principles of my invention.

FIG. 2 is a vertical cross-sectional view taken along line II-Il ofFIG. 1. w

FIG. 3 is a rear view, with parts of the filter cups shown broken away,of the respirator face piece shown in FIGS. 1 and 2 and as viewed fromthe right-hand'side of FIG. 2.

FIG. 4 is an enlarged, elevational view of the exhalation valve seatshown in FIG. 2.

FIG. 5 is a crosssectional view taken along line VV of FIG. 4.

FIG. 6 is an enlarged elevational view of the exhalation valve shown inFIG. 2.

FIG. 7 is an enlarged view of the inhalation valve showing the mode ofsuspension, and

FIG. 8 is a vertical cross-sectional view taken along line VIlI-VIII ofFIG. 7.

Referring more particularly to FIGS. 1 and 2 of the drawings, numeral 1denotes a face piece of rubber or other suitable flexible material andwhich is of generally pear shaped contour, having an inwardly turnedmarginal lip or edge portion 1b along the mouth portion of the facepiece 1. Portion 1b is of reduced thickness and is adapted to provide acushioned contact about the nose, cheeks and chin of the wearer and toprovide an air-tight or dusttight seal. The marginal edge portion lb isdisposed in substantially a single flat plane and has an integral lowerextension 10 which bridges the lower portion of the marginal edgeportion 11b to form a chin rest, as shown more clearly in FIG. 3.

An important feature of the present invention resides in theconstruction and particularly the mounting of the inhalation valves 6and 7. Such valves are suspended from rubber retaining studs 4 and 5,shaped somewhat like rivets, and integrally molded in the face piece 1.As will be noted in FIG. 8, the shanks of retaining studs 4 are disposedat right angles to the portion of the face piece 1 on which they areintegrally molded. Thin rubber diaphragms or valves 6 and 7 are providedwith a pair of holes along the top edges thereof corresponding to thepositions of the studs 4 and 5, and of diameter substantially the sameas that of the shanks of studs 4 and 5, whereby upon stretching of thetop portion of diaphragms 6 and 7 they may be pushed in to clear theheads of the studs whereby the diaphragms may be attached to the shankportions of the studs 4 and 5 and held in place by the heads.

Face piece 1 is provided with a pair of integrally molded inhalationvalve beads or seats, such as 111 and as shown more clearly in FIG. 8,which seats are in vertical planes which are disposed at a slight anglewith the plane of the adjoining upper portion which carries studs .4 and5. As valve 6 unseats from bead 1d, air may be inhaled through circularhole 1e formed on the left front side of the face piece communicatingwith a filtered air space inside cup 2a. A similar inhalation valve portis provided in the right front portion of the face piece :incommunication with filter cup 3. Either filter pad discs or chemicalcartridges may be used, interchangeably in cups 2a and 3a to filter dustor obnoxious fumes. By providing a pair of retaining studs supportingspaced portions of the top part of each inhalation valve diaphragm therewill be no tendency for the diaphragm to rotate. Of course a singleinstead of a double stud may accomplish the same purpose by making anenlarged shank of square crosssection (not shown) if desired. It will benoted that there is no need for other means for supporting thediaphragms 6 and 7 than the retaining studs and molded seats, such as1d.

An important feature of suspending diaphragms 6 and 7 from the top onlywithout further support along the marginal portions is that gravity willassist in keeping the disphragms in their normal downward and seatedpositions as shown in FIG. 8. Furthermore, since air is exhaled from thenose in a downward direction such air will be in the proper direction toapply the necessary pressure to assure seating of the diaphragms d and 7against their seats. Furthermore, since there are no metallic seatelements, there will be no objectionable noise producing vibrations as aconsequence of opening and closing of the valves.

Another provision to facilitate breathing of the wearer and yet assure aperfect seal resides in the particular construction of the exhalationvalve, the parts of which are shown more clearly in FIGS. 2, 4, 5 and 6.The exhalation valve or outlet valve seat 8 is preferably made of hardplastic material such as nylon, and is provided with a rim of channelshaped cross-section which provides a. well 8a forming a seat for themarginal portion of the face piece surrounding the exhalation port, asshown more clearly in FIG. 2. Valve seat 8 is inserted by forcing it inso as to stretch the face piece portion which surrounds the exhalationvalve opening. The outlet valve seat is preferably provided with aplurality of integral sealing ribs or break edges 8b, 8c, and 8d whichare disposed along an arc of a circle, for example, one having a radiusof about 1% inches. A dished outlet diaphragm 9 is provided having athickness of about .02 to .03 inch, which is adapted to become seatedagainst each of the rim portions 8!), 8c and 8d. Diaphragm 9 may be aflat disc but is preferably molded in an arcuate shape so as to have anarcuate cross-section, as shown, but preferably of greater radius ofcurvature, such as, for example, 3% inch radius so that the diaphragmrim portion will be deformed from its normal position to assure constantseating engagement with the break edges 8b, 8c and 8d. Valve 9 hasintegral stem portions 9a and 9b which extend through the central hole 8of the valve seat 8 until the enlarged stop portion 9c becomes seated oncollar portion 8g so as to firmly hold diaphragm 9 in the seatedposition. Only three thin spokes 8e are provided in the valve seat toassure a large area for passage of exhaled air.

It will be noted that should valve 6 have an imperfection, such as aprojection which engages one of the seating edges 8b, 80 or 8d and thusprovide a leakage path or air, the other two edges will neverthelessprevent air flow since, in effect, there are three concentric valveseals. The grooves between the rim portions permit escape of excessivemoisture from the sealing surfaces.

If desired, a marginal head (not shown) may be integrally formed on thetop peripheral portion of valve diaphragm 9. The exhalation valveconstruction is such as to greatly facilitate breaking of the seal uponexhalation of wearer, as well as to allow quick and positive sealingengagement with the respective concentric seats upon inhalation of thewearer, thereby greatly reducing breathing resistance.

As shown more clearly in FIGS. 1 and 2, a nose pleated portion 1a isprovided in the upper or nose surrounding of the face piece 1. Thepleated portion 1a is of reduced thickness, such as of the order of .03inch thick and is preferably in the form of a pair of steps in which theriser portions are about inch high and the tread portions, inch wide.The tread portions are substantially horizontal and the riser portionsare disposed at about 10 with respect to a vertical transverse plane. Asthe pleats are flexed in response to pressure of the marginal portion 1bagainst the nose, the upper part of marginal portion 1b will pivotforwardly about a horizontal axis defined by the extremities of thepleated portion 1a so as to provide a very flexible and very comfortablefit around the nose of the wearer.

An outlet valve guard 10 is provided which is substantially cup shapedand having a radially inwardly turned marginal edge portion 1011 whichis adapted to be seated in an annular groove formed along the perimeterof the exhalation port shown in the lower left end portion of FIG. 2.Thus guard 10 may be seated by forcing it into seating engagement withthe groove in the face piece.

Thus it will be seen that I have provided a highly eflicient industrialrespirator having relatively simple and inexpensive parts which may beeasily and quickly assembled and detached, and which parts are of suchconstruction as to greatly reduce breathing resistance and thus I offlexible material of substantially pear shaped outline,

avoid fatigue of the wearer; furthermore, I have provided a novelinhalation valve suspension which assures easy flexing of the valvediaphragm to the open position and which is so arranged that the valvewill close forcibly with the aid of exhaled air directed in the properdirection; furthermore I have provided an efficient exhalation valveconstruction which will assure positive sealing engagement with at leastone or more of a plurality of concentric sealing rings irrespective ofimperfections in the valve diaphragm or seats.

While I have illustrated and described a single specific embodiment ofmy invention, it will be understood. that this is by way of illustrationonly, and that various changes and modifications may be made within thecontemplation of my invention and within the scope of the followingclaims.

I claim:

1'. In an industrial respirator comprising a face piece a pair of filterboxes secured to the exterior of the enlarged sides thereof, a pair ofinhalation valves mounted on the interior surface of said face piece incommunication with said filter boxes, each of said inhalation valvescomprising a thin, flexible valve diaphragm and a pair,

of suspending stud elements located in close, side by side relationshipabove the diaphragm and integrally secured to the inner surface of theface piece, there being no other valve fastening elements, wherebysubstantial flexing of said diaphragm and minimum breathing resistanceare provided;

2. A respirator as recited in claim 1 wherein said face piece hasinhalation valve ports which have beads integrally molded on said facepiece along the marginal portions thereof which form seats for theinhalation valve diaphragms.

3. A respirator as recited in claim 1 wherein said inhalation valve studelements are in the form of rubber rivets having shank portions, a pairof holes substantially the same diameter as said shank portions formedin the top of each inhalation valve diaphragm through which the shanksof said stud elements extend.

4. A respirator as recited in claim 1 together with an exhalation valvein said face piece comprising a detachable, wheel-like valve seat havinga rim portion of substantially U-shaped cross-section attached to theperipheral portion of an exhalation valve opening in the lower frontportion of the face piece.

5. A respirator as recited in claim 4 together with a groove integrallyformed in said face piece and extending about the exhalation valvetogether with a valve guard of substantially cylindrical cup shapehaving an inner marginal edge portion which is adapted to project intosaid groove to form a slip-fit therewith.

References Cited in the file of this patent UNITED STATES PATENTS922,262 Clemens May 18, 1909 1,310,119 Harper July 15, 1919 2,036,850Bullard Apr. 7, 1936 2,378,613 Young et a1. June 19, 1945 2,738,788Matheson et a1 Mar. 20, 1956 2,744,525 Whipple May 8, 1956 2,744,539Jones May 8, 1956 2,745,133 McWethy May 15, 1956 2,818,861 Russell Ian.7, 1958 2,858,828 Matheson Nov. 4, 1958

